NAND Flash, What Comes Next?

Samsung introduced the first solid-state drive employing the 3D flash memory. This technology involves turning the chip on its side and moves from today’s 2D flash technology to 3D. This technology is also known as V-NAND, and it will be twice as fast as NAND for both reads and writes, as is now sampling with 480 and 960 GB capacities.

SMART Storage Systems in partnership with Diablo Technologies introduced the ULLtraDIMM. The ULLtraDIMM flash storage is placed directly on a system’s DIMM sockets and brings latency down to 5 microseconds, and comes in capacities of 200 and 400 GB. This product will bring a new paradigm to applications requiring very low latency storage.

Flash prices are continuing to fall, and capacities continue to increase. Marvell Semiconductor Vice President of SSD Iri Trashanski speaking to attendees, noted that the cost of flash memory which was $12/GB in 2007 is down to $0.60/GB in present 1 TB SSDs, and is expected to fall to $0.30/GB in 2016, when SSDs will offer up to 2 TB of capacity per drive.

NAND flash in all its form factors is booming in the enterprise, and will enjoy increasing commercial penetration. The latest price drops will make its adoption even more compelling. So what comes next? Three new technologies are already on the horizon: phase-change memory (PCM), magnetoresistive RAM (MRAM), and resistive RAM or (RRAM).

About two years ago, IBM Research announced PCM, and inferred that systems built from this type of technology could fetch data 100 times faster than NAND flash, and be rated for 10M write cycles. This is 100 times the endurance of SLC NAND flash, and more than 300 times the endurance of eMLC. These products could become commercially viable by 2016, and Big Data analytics is one of its target markets. Speed of adoption is going to depend on cost of this technology. Aside from IBM, Intel, Micron and others are also exploring this technology.

MRAM technology is also under exploration by various research groups including Micron, Intel, Toshiba, and Samsung. This technology is several years away, and the semiconductor processes are still in larger form factors, greater than 150 nm, compared to the 19 nm flash products shipping today. But it’s fast and non-volatile, and could replace not only NAND, but DRAM and SRAM as well.

RRAM, also known as memristor has been generating lots of interest recently. Compared to NAND flash this technology is expected to consume 95 percent less power, perform writes 20 times faster, and have a life of 10,000 write cycles, which is three times the life of consumer grade MLC, but only one third the life of eMLC. However, it shows promise in that it consumes very low power, has a low cost of manufacturing, and the die is half the size of current flash. Santa Clara startup Crossbar, Inc. emerged from stealth mode at the summit and presented this exciting development in New Technologies Track at the summit.

All in all, Flash is a crowded market with host of disruptive technologies waiting in the wings. Things are going to get very interesting in the next few years.